Car starts then turns off

[DC2-PWR]

Hey,

my car starts fine, but then just after it turns on, it dies.

what i did notice, lastnight my cars dash light was slowly dieing, but after ahwile it goes back to normal.

I played with the ignition, when I turn the key to II, the dash lights wont come on. But when i slowly turn it back to I, it turns on.

Video

Sparkplugs changed lastweek
o2 sensor chaned lastweek

Please help.